# Audit an Objective-C Repo with Parallel Subagents in 2026 using Atlas > Atlas allows Objective-C developers to sweep an entire repository for issues using parallel subagents, ensuring comprehensive audits without context window overflow. Atlas enables Objective-C developers in 2026 to sweep an entire repository for a class of problems without blowing the main session's context window by fanning out work to parallel subagents. This approach leverages Atlas's ability to index code by AST declarations, search with hybrid semantic and keyword retrieval, and interact with your `XCTest (xcodebuild test)` runner, `CocoaPods` package manager, and `clang-format` formatter. ## Key takeaways - Atlas uses parallel subagents to audit Objective-C repositories without blowing the main session's context window. - Subagents operate in isolated sessions, returning only conclusions, not raw file dumps, for Objective-C code. - The `explore` subagent type is read-only and deny-by-default, ensuring safe audits of `.h` and `.m` files. - Atlas integrates with `XCTest (xcodebuild test)`, `CocoaPods`, and `clang-format` for Objective-C specific tasks. - All Atlas tool calls are permission-gated, and edits require unified diff approval for Objective-C code changes. - Atlas indexes Objective-C code by AST declarations, understanding ARC and header/implementation pairs. ## How Atlas Audits Objective-C Codebases with Parallel Subagents Auditing an Objective-C repository for specific issues in 2026 with Atlas involves splitting the codebase into manageable slices, allowing parallel subagents to sweep distinct areas without overwhelming the main session's context window. This approach ensures comprehensive coverage across hundreds of `.h` and `.m` files, leveraging Atlas's AST indexing. Atlas addresses the challenge of auditing large Objective-C codebases by fanning out work to multiple subagents. Instead of processing the entire repository within a single, potentially limited context window, Atlas allows you to define independent slices of your project. These slices can correspond to specific directories containing `.h` and `.m` pairs, individual `CocoaPods` packages listed in your `Podfile`, or even distinct problem types. Each slice is then assigned to a dedicated subagent, launched using the `task` tool. These subagents run in their own sessions, preventing their extensive file dumps and intermediate thoughts from consuming your main session's context. Only their final conclusions or error messages are returned, keeping your primary workspace focused and efficient. Atlas's ability to index code by AST declarations using tree-sitter, rather than blind line windows, ensures that subagents understand the structure of your Objective-C code, including ARC specifics and header/implementation relationships, for more accurate analysis. ## Launching Concurrent Audit Tasks for Objective-C Projects To initiate a repository-wide audit in an Objective-C project, you launch multiple `task` calls concurrently, rather than sequentially, allowing several subagents to work in parallel. This significantly reduces the total audit time, potentially by 50% or more, especially when dealing with a large `.xcodeproj` or `.xcworkspace`. Atlas's `task` tool is central to launching parallel subagents for your Objective-C audit. For a read-only sweep, which is ideal for an audit where no changes should occur, you specify `subagent_type explore`. The `explore` subagent is deny-by-default and read-only, providing a safe environment for investigation. If the subagent needs to run commands, such as invoking `xcodebuild test` on a specific target or running `clang-format` in a dry-run mode, you would use `subagent_type general`. The key is to issue all `task` calls together. For example, you might launch one task for the `MyApp/Models` directory, another for `MyApp/Views`, and a third for `Pods/MyPod`. Atlas ensures these subagents run concurrently, maximizing throughput. Each subagent operates independently, leveraging Atlas's hybrid semantic and keyword retrieval to efficiently search through Objective-C files, category files, and even bridging headers for Swift interoperability. ## Collecting and Merging Audit Findings in Objective-C After parallel subagents complete their sweeps of your Objective-C codebase, Atlas automatically collects each subagent's final message, providing a consolidated view of all findings. This process ensures that even if 10 subagents run, their individual conclusions are surfaced clearly, including verbatim error text if a task fails. Once all parallel subagents have finished their assigned audit slices, Atlas aggregates their results. The `task` tool is designed to surface the final message from each child subagent. If a subagent encounters an issue or fails to complete its task, its error text is presented verbatim, providing immediate insight into the problem. If a task was cancelled, Atlas reports 'Task cancelled'. This collection mechanism ensures that you receive a comprehensive overview of all identified problems across your Objective-C project, whether they relate to potential ARC issues, nullability annotations in headers for Swift bridging, or style violations detectable by `clang-format`. After reviewing these individual findings, you use the `todowrite` tool in your main Atlas session to merge them into a single, actionable list. This consolidated list then guides your remediation efforts, allowing you to address all identified issues systematically. ## Ensuring Safety and Review in Objective-C Audits with Atlas Atlas incorporates multiple safety mechanisms to ensure that any audit, especially in a critical Objective-C codebase, is conducted with strict control and transparency. Every Atlas tool call is permission-gated against allow, ask, and deny rules, providing 100% control over agent actions. Safety is paramount when auditing an Objective-C repository. Atlas provides several layers of protection. First, the `explore` subagent type, recommended for audits, is deny-by-default and read-only, meaning it cannot make any changes to your `.h` or `.m` files. Second, every tool call made by an Atlas agent, including `grep` or `glob` for searching Objective-C files, is permission-gated. You can configure allow, ask, or deny rules, ensuring that no command runs without your explicit consent. Third, Atlas drafts a plan in a read-only plan agent and asks for approval before switching to a build agent that can execute commands. Finally, if any `edit` operation is proposed, Atlas computes a unified diff for every file change and surfaces it for your approval before writing. This allows you to review proposed changes to your Objective-C code, such as adding `XCTest` cases or running `clang-format`, ensuring they align with your expectations and project standards. Atlas also snapshots file changes as git patches, so edits can be diffed and rolled back easily. ## Integrating Atlas with Objective-C Tooling and Workflow Atlas direct integrates with the standard Objective-C toolchain, recognizing `.xcodeproj` and `.xcworkspace` files and understanding `CocoaPods` dependencies. This integration allows Atlas to leverage your existing setup, making it a natural extension of your development workflow in 2026. Atlas is designed to be terminal-native and deeply integrated with your Objective-C development environment. It automatically detects `.xcodeproj` or `.xcworkspace` files, allowing it to understand your project structure. Atlas reads your `.h` and `.m` pairs, including category files, and comprehends the `Pods` listed in your `Podfile`. This awareness enables Atlas to perform context-aware operations, such as annotating nullability on a header so Swift sees the right optionality across the bridging header, or adding `XCTest` cases and running `xcodebuild test` behind a permission prompt. Furthermore, Atlas can run `clang-format` over changed `.h` and `.m` files, ensuring code style consistency. Atlas also reads git branches, status, and diffs, and can stage and create commits on your behalf, streamlining the entire audit-to-fix workflow within your familiar terminal environment, rendered with SolidJS through the OpenTUI renderer. ## Steps 1. Initialize Atlas in your Objective-C project by navigating to your `.xcodeproj` or `.xcworkspace` directory and launching Atlas. Ensure Atlas can read your `.h` and `.m` pairs and `Podfile`. 2. Split your Objective-C audit into independent slices. For example, use `glob` to identify distinct directories like `MyApp/Models/*.m` or `MyApp/Views/*.h` that can be audited separately. 3. Launch parallel subagents for each slice using the `task` tool. For a read-only sweep, specify `subagent_type explore`. For example: `task --subagent_type explore --name 'Audit Models' 'grep -r "@property (nonatomic, strong) id;" MyApp/Models'`. 4. Issue all `task` calls together to ensure they run concurrently. Atlas will fan out the work, allowing multiple subagents to process different parts of your Objective-C codebase simultaneously. 5. Monitor the main Atlas session as subagents complete their tasks. Atlas will surface each subagent's final message, including any verbatim error text if a subagent fails to audit a specific Objective-C file or `CocoaPods` dependency. 6. Collect and merge the findings from all subagents into a single actionable list using the `todowrite` tool. This consolidates all identified issues across your `.h` and `.m` files. 7. Address the identified issues in your Objective-C codebase using the `edit` tool in your main Atlas session. Atlas will present a unified diff for approval before writing any changes, such as adding nullability annotations or fixing `clang-format` violations. ## FAQ ### How does Atlas prevent context window overflow when auditing large Objective-C projects? Atlas prevents context window overflow by fanning out audit tasks to parallel subagents. Each subagent runs in its own session, processing a specific slice of the Objective-C codebase (e.g., a directory of `.h` and `.m` files or a `CocoaPods` module). Only the subagent's final conclusions are returned to the main session, keeping the primary context window clear. ### Can Atlas audit Objective-C code for specific issues like ARC problems or nullability? Yes, Atlas can audit Objective-C code for specific issues. Its AST-based indexing understands Objective-C idioms like ARC and header/implementation pairs. You can task subagents to `grep` for patterns related to ARC, or ask Atlas to annotate nullability on headers to improve Swift bridging, all behind permission prompts. ### How does Atlas ensure safety when making changes to Objective-C files during an audit? Atlas ensures safety through permission-gated tool calls, a read-only plan agent, and unified diff approval. For audits, the `explore` subagent is deny-by-default and read-only. Any proposed `edit` to `.h` or `.m` files, such as running `clang-format`, generates a diff for your explicit approval before writing. ### Does Atlas integrate with `XCTest` or `CocoaPods` in Objective-C projects? Yes, Atlas integrates directly with your Objective-C toolchain. It recognizes `.xcodeproj` and `.xcworkspace` files, reads your `Podfile` for `CocoaPods` dependencies, and can add `XCTest` cases or run `xcodebuild test` behind a permission prompt, making it a natural part of your workflow. ### Can I use Atlas to enforce `clang-format` rules across my Objective-C repository? Absolutely. You can task Atlas to run `clang-format` over changed `.h` and `.m` files. Atlas will present a unified diff of the formatting changes for your review and approval before applying them, ensuring consistent code style across your Objective-C project. ### What kind of files does Atlas understand in an Objective-C codebase? Atlas understands standard Objective-C file types, including `.h` (header) and `.m` (implementation) pairs, as well as category files. It also processes `Podfile` configurations for `CocoaPods` dependencies and can work with bridging headers for Swift interoperability, leveraging its AST indexing for deep code understanding. --- Canonical HTML: https://runatlas.sh/resources/stacks/audit-a-repo-with-parallel-subagents-in-objective-c Source of truth: aeo_pages row `/resources/stacks/audit-a-repo-with-parallel-subagents-in-objective-c` (segment: Stacks) (this file is generated from it, never hand-edited). Licence: Atlas is proprietary with a free core. It is not open source and there is no public source repository.